Green-veined White. Photo: Penny Hawes

Green-veined White. Photo: Penny Hawes

Penny did well to catch these two Green-veined Whites in Bournemouth Gardens on 20/07/2017. She is probably right in thinking the female is in a mating refusal posture. Some butterfly species have evolved this behaviour so that when the female is already mated she refuses the male, allowing her to get on with laying her fertilised eggs. This is done by her holding her wings wide open and raising her abdomen almost to a vertical position, often with the genitalia extruded.